The present invention relates to a catheter that can be placed into the body for drainage of one of its parts. Parts of the body that can be drained using the present catheter include organs, abscesses, ducts, biliary and urinary tracts and cavities such as the chest or abdominal cavity. The present invention especially relates to a catheter having an outer tubular member and an inner tubular member slidably disposed in the lumen of the outer tubular member. The inner tubular member can be withdrawn from the outer tubular member to remove encrustations which form and can block the required drainage.
Most commonly, catheters of the prior art are fully removed from the body part being drained because encrustations in the lumen or at the inlet port which prevents the passage of fluids. A new catheter is then inserted in the old one's place and will remain there until it too becomes blocked or is routinely changed. Replacement of catheters not only is costly from the standpoint of service time and cost of the catheter but potentially it can be difficult procedurally because access to the part being drained can be lost during exchange procedures. An alternative approach described in the art is the use of a pusher or brush to clear the lumen. Such procedures are not commonly used because the encrustation may be pushed back into the drainage site and/or the force necessary to dislodge encrustations may result in the pusher puncturing the side of the catheter. Another procedure used to reduce encrustation is to introduce biodegradable particles and drugs into the body. Since some drugs produce allergic reactions and dosage considerations are difficult to resolve and because of a short life span such procedures have not been widely used.